Oil burner



F. HARDINGE oIL BURNER Filed Nov. 2, 1928 WHW M v 473 17 ir Il Nov. 12, 1929.

Patented Nov. 12, 1929 'UNITED STATI-:s PATENT lor-Fic FRANKLIN HARDINGE, Ior CHICAGO, ILLINOIS, Ass'IGNon *ro HARDINGE BRo'rHERs,

INC., oF CHICAGO, ILLINOIS, n eoIzPonATioN or `ILLINo'Is oIL BURNER Application led November My invention relates to oil burners of the centrifugal atomizer typeand is concerned especially with yan improved feed for the fuel oil from a stationary fuel supply member on to the rotary atomizer. n j f My present invention may be considered ask an improvement on that disclosed in my co-pending application Serial No. 7 48,862, :filed November 10, 1924.

As compared with the structure disclosed in that application, the object of my present improvement is to eliminate the tendency of oil passing the narrow annular gap between the stationary feed Kmember and the rotary feed member of the -atomizer lfrom traveling downwardly along the fuel delivery Ista-nd pipe.

Another object of my invention is to provide for the vertically journaled atomizer a cover which'will prevent dirt from dropping down into the mouth of the atomizer but will not interfere with cleaning of the interior of the atomizer. f

These and further objects, featuresy and advantages of my invention are set forth in the following description of a specific embodiment thereof as illustrated in the accompanying drawings wherein:

Fig. 1 isa cross section through my oil burner as installed in thecombu'stion chamber of a boiler;

Fig. 2 is a detail section enlarged from Fig. 1 and showing the structure for effecting the oil feed from the fuel supply conduit'on to the rotary atomizer; f

Fig. 3 is a transverse plan section taken on line y3-3 of Fig. 2; and y Fig. 4 is a greatly enlarged detail section taken from Fig. 2. f 1 n A hollow spindle 10 is journaled by ball bearings k11 in a gear casing or body 12, and is driven through the bevel gears 13'by a horizontal drive shaft 14 extending from an electric motor or other source of power not shown. rThe gear case 12 is placed in the ash pit of a boiler beneath the floor of the kcombustion chamber, and carries at its upper end an atomizer 15 which protrudes through the bottom of a dish-shaped fire pot 16, thus forming the floor of the combustion chamber.y At

2, '1928. 'serial No. 316,677.

its `"upper endthejatomizer 15 is outwardly flared to :form a discharge lip beneath which are radially arranged sirocco fan vanes 17 generating `a horizontal outward primary air supplyI beneath the `dischargelip of theatom iz'erf. The path of the air emanating from these sirocco fan 'vanes is controlled by an air ring 18 the inner 'margin of which acts as abloclr-'offring rto'regulate the air. The air ri'ng18 '1s vertically vadjustable by a support ingcam ring 19, the lower periphery of which rests on a set'of rollers 20 fixed on a stationary hearth rin'g 21. Suitable means may be supplied for rotating the cam ring 19 from with'- out the furnace walls for effecting the vertical adjustment of the air ring 18. `Such vertical adjustment also varies the openingr in the annularly arranged ports 22 beneath the outer edge of the air ring 18. This provides a variable auxiliary airV supply 'preferably under rnatural draft. n f n The hearth ring 21 andthe fire pot 16 may kbe supported by suitable posts 23 and pref# erably independently of the gear case 12 so that vibration of the latter is not imparted to they combustion chambers.

y Fuel oilfor the burner is fed from a source of supply through a rpipe 25 and into a base member 26 from which it passes rthrough an upwardly extending standpipe 27. The pipe 25, base member 26 and standpipe 27 are preferably mounted more or less independently. from the gear case 12 to lessen danger of vibration and alsoto permit the case 12 and its yassociated parts to be lifted upwardly from the `standpipe'when dis-assembling the ingy 'cap 28 whichforms 'a continuation ofthe o bore of the standpipe 27 does not extend through the top of the cap but communicates `with three obliquely and radially drilled ducts 29, which lead to the periphery of the' capV above ay slightly shouldered cylindrical portion 30.- f I The eto'mzer 15 preferably carries a corresponding shoulder 3l on the inner' surface of its throat. and laterally opposite the shouloer of the stationary cap. A very slight annular cylindrical space is thus left between the shoulder of the portion 30 of the stationary cap and the corresponding portion of the throat of the atomizer. The atoniizer rotates at so high a rat-e of speed that the oil as it flows on to the upper face of the shouldered portion 30 is immediately drawn across the intervening gap on to the interior surface of the atoinizer. VThe shoulder 3l of the atomizer offers an immediate outward rotary travel for the oil under centrifugal action to accelerate the flow of the oil across this intervening gap. i From this peint the oil flows upwardly along the slightly tapered interior wall of the atomizer under centrifugal action.

As a result of this method of feed the oil is transferred from the stationary feed ineinber on to the rotary atomizer member in substantially a continuous lilm and over an annular region, as distinguished from being transferred in drops. The advantage of this continuous action is that it will sustain a continuity of the oil flow at very low feeds in gallons per hour, and enable a low nre to burn evenly and without interruption.

To prevent the leakage of lubricant from the gear case 12 on to the lower part of the pipe 27 and its associated parts, and thence on to the floor of the ash pit, l provide an upstanding tube 32 extending from a fluid tight fit in the bottom wall of the gear case l2 to a point not far below the upperv end of the standpipe. A thimble member 32 is secured tor the inner surface of the upper end of the spindle 10 and has upper and lower tubular portions extending at a spaeeins wardly from the bore of the spindle. The lower of these-Brl-extends into the up- 1)er end of the stationar 1 tube 32. The u Jer l Il Y 1 l er these-32Bwextenusf substantially to the i bottoni edge ofthe distributing cap 28 and forms, together with the lower inner wall of the throat of the atomizer, an annular lpocket 33 in which will be trapped any un atomized oil which` dra-ins back kfrom lthe f walls of-the atomizer after the atomizer the stationary tube 32 and the standpipe 27 ,c

whence it will flow out through the Vannular bottom opening 35 in the gear case l2 and on to the door of the ash pit. Such oil will no# dilute the lubricating oil in the case l2.

vin `view of the fact that trie n'ieinber 3T 2B lsrotating at a l The bottom opening 35 of the casing, the space between the standpipe 27 and the stationary tube 82 and the thirnble 32 forms a central air passage for the upward flow of air along the exterior of the standpipe 2i'. lt will be noted that the air passage is radially without the oil passage below the point of oil transfer. Above the point of oil transfer the oil will have to be radially without theair. The air and oil inust therefore radially cross each others path at the point of the oil transfer from the stationary feed cap to the rotary atoniizer. This crossing over of the air and oil should preferably be done without bringing the two into cont-act, lest the air prematurely vaporize the fuel or at least interrupt the continuity of its dow.

l have solved this problem by providing a set of vertical air passage holes 36 through the standnioe distributor cap radially without the central bore thereof and arcuately between the ducts 29 thereof.

This central air supply serves to cool the spindle and the interior of the atoinizer and counteract any ill effects from the heatr of the combustion chamber to which it is more or less subjected. Passing the air through holes in the distributor cap aords an effective means for keeping the cap cool. This is especially important because were the cap to become excessively hot it wouldv carbonize the fuel oil in its small passage ways and build up deposits which would soon close them, seriously iinpairing the fuel supply.

My burner as thus lfar described is substantially identical with that disclosed in my above mentioned co-pending prior applica tion.

l have found, in the structure of my prior application, some tendency of the air passing upwardly through the thimble 32 and the air passages 36 inv the head Lto draw in air from the annular pocket 33. This would cause a partial vacuum in the poclret 33 and tend to pull down the oil passing' over the annular gap between the stationary and rotary transfer members. As a result l find that fuel oil would be carried down to the under side of the head 28 and into the air passages 36, whence it would be deposited on the head and trickle down into the space between the thirnble 32 and the standpipe 27 and from there through the bottom opening 35 and on to the floor of the ash pit. To remedy this I have restricted the effect-ive opening from the annular pocket 83 into the passage for upwardly flowing air. l have done this by providing an auxiliary sleeve 37 which securely lits over the bottom edge of the cap 28 and extends downwardly parallel 'to the upper end of the portion 32B of tl e thiinble lOl) lli)

32 but at a very slight distance the efrom.

Y This permits a sufficient practical clearance s stationary and the member insana high rate of speed,butthe relative vertical sleeve 37 be turned inwardly somewhat fur- `ther to restrict the opening.

, As a result I find so far as anyftendency 'to cause leakage isconcerned the pockct is sufficiently air tight. However, a sufiicient working .clearance is allowed for the relative rotation of the two parts and there is sullicient air passage to permit of the vexhausting under centrifugal force of any fuel oil which collects in the pocket 33. y f

As a further improvement in my burner I provide a cover member. This cover member is not only for an insulating effect but a protection for the fuel transfer mechanism against dirt or other foreign matter falling down into the throat of the atomizen For this purpose `'I provide a socket member 41 on the upper endl of the distributor cap 28. The lower end of the stem 42 is taper fitted into this socketand at a pointabout opposite that at vwhich the atomizer starts to taper upwardly and outwardly, the stem carries a cup 43. The stem extends upwardly beyond the cup 43 and supportsy a larger cup 44. While both cups 43 and 44 may be employed, as I have'shown in Fig. 1, it is not necessary that both be employed, and either one or the other may be `used alone. I

The upper cup 44 is spaced sufficiently away from the lip yof the atomizer to permit a certain cleaning of the atomizer without removing'the cup. For cleaning, the cups alone or the ycups andthe stem may be removed. If the cu 44y is noty used, butfonly the cup 43 is used the cup 43 will form a convenient stop for the cleaning rod which will preventthe cleaning rod being inserted farther' down in the throat of the atomizer than carbon deposits customarily occur under adverse conditions. y

While I have thus described my inventio in the particular embodiment shown, I contemplate that many changes may be made therefrom without departing from the scope or spirit of my invention.

I claim:

1. An oil burner comprising a vertically positioned rotary nozzle having an upwardly and outwardly tapering discharge opening, a stationary oil supply conduit extending into the interior of the nozzle, a stationary tip for said conduit having an annular distributing surface extending outwardly from the tipy closely to the inner wall of the nozzle, means i for conducting oil from the conduit to said annular distributing surface, said surface distributing oil directly onto the inner wall of the nozzle, a thimble rotating with the nozzle and having anupwardly extendingportion spaced from said conduit, and adepending sleeve on saidtip extending closely to said upwardly'extending portion of the thimble for substantially preventing the passage of air therebetween.

- 2. An oil burner comprising a vertically positioned rotar nozzle having an inverted bell-shapedr disc arge opening, a spindle for rotating said nozzle, an oil supply standpipe `extending to the interior of said nozzle, a cap for said standpipe having an annular distribbuting surface extending outwardly closely,

to they inner wall of the nozzle, means for conducting oil from said standpipe to said annu-k lar distributing surface, air passageways extending vertically through said cap,y and means for substantially pre-venting the crcation of a vacuum in the space immediately below said distributing surface. f

y3. yAn oil burner comprising a vertically positioned rotary nozzle having anv inverted bellshaped discharge opening, a spindle for c rotating said nozzle, an oil supply standpipe extending to the interior of said nozzle, a cap for saidy standpipe having an annular distributing surface extending outwardly closely tothe inner wall of the nozzle, means for conducting oil fromsaid standpipe to said annular distributing surface, vertical air passages through said cap, a thimble in said spindle, having extensions ythereon forming an air passageway along saidstandpipe, leading to said vertical air passages, and a depending sleeve on said cap extending along and adjacent `the upper extension of said thimble for substantially preventing the flow of 'air therebetween, n

4. A11 Oil' burner comprising a vertically positioned rotary atomizer having any invert edfbell-shaped discharge opening, a spindle for supporting and rotating said atomizer, an oil supply standpipe extending to the interior of said atomizer, a cap for said standpipe having an annular distributingr surface expassages through said cap above said passageway, an extension on the upper end of said thimble spaced from said spindle andforming an annular oil receiving pocket, and a sleeve fitted to the lower end of said cap and extending r closely to saidextension for substantially preventing the circulation of air through said pocket. v .c

n 5. An oil burner comprising a vertically positioned rotary nozzle having an inverted bell-shaped discharge opening, a spindle for .rotating said nozzle, an oil supply standpipe extending to the interior of said nozzle, a cap for said `standpipe having van annular distributing surface extending outwardly closely to `theinner wall of the nozzle, means for IUJO conducting oil from said standpipe to said annular distributing surface, vertical air pas sages through said cap, a thimble in said spindle having extensions thereon forming an air passageway along said standpipe leading to said vertical air passages, a sleeve snugly fitted to the lower periphery of said cap below said distributing shoulder and on a vertical line with the outer edge thereof, said sleeve having a horizontal portion seated on the lower edge of said cap, and a depending portion extending along said thimble extension in close proximity therewith, the extreme lower end of said sleeve being turned toward said extension for further restricting the passage therebetween.

6. An oil burner comprising a vertically positioned rotary atomizer having an inverted bell-shaped discharge opening, a spindle for supporting and rotating said atomizer, an oil supply standpipe extending to the interior of said atomizer, a cap for said standpipe having an annular distributing surface extending outwardly into closeV proximity with the inner wall of the atomizer, means for conducting oil from said standpipe to said annular distributing surface, a thimble in said spindle spacedl from said standpipe and forming an air passageway threrealong, vertical air passages through said cap above said passageway7 an extension on the upper end of said thimble spaced from said spindle and forming an annular oil receiving pocket, and means on said cap surrounding the upper end of said extension for substantially preventing the movement of air upwardly through said vertical passages, from evacuating said pocket. l

7. In an oil burner the combination of a vertically mounted, rotary Vnozzle having an upwardly and outwardly tapering discharge opening for atomizing liquid fuel, a lfuel supply standpipe extending into the interior of the nozzle, fuel transfer means on said standpipe, cooling means for said nozzle, comprising, air passageways admitting an upward draft of air through said nozzle, an oil receiving pocket below said transfer means and a'depending sleeve extending into said pocket at the inner side thereof for preventing the upward draft ofair from causing 4a circulation of air through said pocket.y

8. In an oil burner'the combination of 'a vertically mounted, rotary atomizing nozzle having Van upwardly and outwardly tapering discharge opening for atomizing liquid fuel, a spindle for supporting and'rotating said nozzle, a ystationary fuel supply standpipe extendinginto the interior of the nozzle, an annular fuel distributing surface for said Jstandpipe, the periphery of said surfacey eX- tending sufhciently near the inner surface of the" rotary 'atomizer that the fuel is caused to flow horizontally across the open space therebetween, means fork directing an upward flow of air through said spindle and said atomizer, a pocket beneath the open space across which the fuel flows, and a stationary sleeve depending along the upper end of said air directing means for preventing the evacuation of said cup and the drawing of fuel downwardly through said open space.

9. In an oil burner the combination of a vertically positioned rotary atomizer, having an upwardly and outwardly tapering discharge opening, for atomizing fuel oil, a spindle for said atomizer, an oil supply standpipe extending to the interior of said atomizer, a stationary distributing cap for said standpipe, having an annular distributing surface extending outwardly toward the inner wall of the atomizer and forming an annular air gap therebetween, said air gap being of such size that oil flows directly and horizontally across the gap from the distributing Cap to the atomizer, a thimble in said spindle spaced from said standpipe and forming an air passageway therealono', vertical air passages through said cap above said passageway, an extension on the upper end of said thimble spaced from said spindle and forming an oil receiving pocket, means on said cap depending along said extension for preventing the upward movement of air through said passages, from evacuating said pocket and drawing oil down through said air gap.

In witness whereof, I hereunto subscribe my name this 26th day of October, 1928. n FRANKLIN HARDINGE. 

